CVE-2026-84309: pypdf: Possible infinite loop for TreeObject.insert_child

September 1, 2026

An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires a (usually writing) code path where TreeObject.insert_child is involved.

References

github.com/advisories/GHSA-jp53-mhqp-8xcg
github.com/py-pdf/pypdf/commit/c9ba557d565d57c53a0b3a0be06c0a4c29b0559b
github.com/py-pdf/pypdf/pull/3964
github.com/py-pdf/pypdf/releases/tag/6.16.0
github.com/py-pdf/pypdf/security/advisories/GHSA-jp53-mhqp-8xcg
nvd.nist.gov/vuln/detail/CVE-2026-84309

Code Behaviors & Features

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